Hikaru had the dream of being a world explorer and he traveled with his parents who were musicians on tour. However when he was 17, he had begun having visions of a great battle and he returned to his childhood home to look for answers. There he met Ultraman Taro who was a Spark Doll, who explained to him that the visions he was having were of the Dark Spark War which was caused by the dark hand and that he was the prophesied hero who would defeat this unseen enemy.